Small tracked robot

I'm finally able to share a photo of my tracked robot:

http://www.flickr.com/photos/24299497@N05/2304988761/

Despite having put encoders on the drive wheels, I still haven't written any code that would make the thing run straight (code that incorporates feedback to drive each side at a matching speed). And now that I'm back in classes I probably won't be doing it soon, either. Especially since I want to use C++ behaviours, as per the playground article http://www.arduino.cc/playground/Code/Behavior. Comments Please!